MC_CMD_SET_MAC is privileged and can only by called by the link
control function.

This patch adds efx_ef10_mac_reconfigure_vf which avoids the call
to MC_CMD_SET_MAC by the Virtual function
Signed-off-by: NShradha Shah <sshah@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>